FEC model for reference only.
Metal clad high-frequency capacitance of the short and thick with a minimum lead inductance.
Input circuit of the inductor coil can be smaller, but in order to make convenience, and the output circuit using the same large coil.

Preparing a 100 x 85mm double-sided printed circuit board (PCB).
Drill a FETFET power tube to pass through the holes.
In the 4-6 drill holes on the PCB to be shielded PCB fixed on the cast aluminum box.
How to design a good device, a fixed heat sink and fan.
In the cast aluminum shield box set power supply, input and output sockets needed holes.
Reference to the photos and schematic in the PCB cut out the welding zone. PCB on the back and positive most of the area is ground.
Welded components.
Part of the output low-pass filter with copper (or the printed circuit board) and the amplifier circuit part of the shield separated.
Output low-pass filter function: filter is used to filter high harmonics, and to reduce the interference caused by nearby radio station, which is important for high-power RF output. For example, suppose the third harmonic of the amplitude ratio is-30dB. When the 1W amplifier when the harmonic power is 1mW, nothing; but when the amplifier is a 40W harmonic power is 40mW, interference is a problem. The circuit harmonic suppression greater than 50dB. If you do not involve tampering with the problem, you can not output low-pass filter.

Debugging

Bias adjustment:

Input with 50 Ohm resistor short-circuit (Note: This circuit is not the case then the input would be self-excited oscillation) will be transferred to the middle of all the variable capacitor will be transferred to R1 voltage minimum. Connected to the +28 V power supply, the current should be 14mA this time around. Adjust R1 so that power supply current of 115mA. If you find a sudden increase in current is a lot of shows that self-excited oscillation circuit requires more shielding isolation.

If you have a RF spectrum analyzer and network analyzer can be used to adjust these instruments. Without these devices it does not matter; in the input through the FM transmitter to join 500mW-1W RF signal, the output of a 50W Dummy Load Termination and, through a 40dB attenuation of a RF power meter Used for measuring output power. If you do not have RF power meter, just on the right side of the detector circuit with the measurement of the voltage monitoring points. To set the transmitting power of transmitters to regulate the fine-tuning capacitor C1, C2, C4, C11, C12, so that maximum output power amplifier.